The easiest response could be: SpaceFiber is a multi-Gbits/s, on-board network technology for spaceflight applications which complements well known SpaceWire network and both are for the satellites that, what Ethernet for us on the ground.
An ASIC is an application specific integrated circuit, which is usually designed to cover a need of functionality or performance (speed, power consumption, dimensions, etc.) that cannot be achieved by a combination of preexistent integrated circuits. The design of an ASIC implies the interoperability of complex tools. In the figure, it can be observed a simplified flow for a low power mixed-signal ASIC design, where both the digital and analog flow will converge via open access.
Application Specific Integrated Circuits or ASICs are non-standard integrated circuits that are designed for a specific use or application. Here a complete system or product is integrated onto a chip and virtually no other components are required. Its function cannot be changed to anything else because its circuitry is made up of permanently connected in silicon. The cost of designing an ASIC is very high, NRE (Non-Recurring Engineering) cost, and therefore they tend to be reserved for high volume products. But ASICs can be very cost effective for many applications where they are produced in large scale.
The evolution of power distribution in the spacecraft goes into a modular architecture direction. Especially the secondary power distribution from the satellite bus to the modules can be made more efficient by applying modular design and standard power interfaces.
In modern satellites, the secondary power conditioning unit must supply a wide variety of low voltages, which are required by the payload modules, precisely and without fluctuations even at severe load variations.